The standard procedure for making B-stageable resins is to dissolve a high molecular weight resin in a solvent. When the solution is applied to a substrate and is heated, the solvent evaporates which leaves a dry coating on the substrate. When heat is applied at a later stage it causes the resin to flow so that it may be used as an adhesive. Additional heat then cures the resin to a permanent hard state.
This technique has several aspects to it which are less than desirable, particularly the production of volatile vapors and the lack of control of the curing mechanism during the drying step. The volatile vapors represent a loss of solvent and may constitute a pollution problem. When the substrate is paper the solvent removal step also removes water from the paper which leads to its embrittlement.